Improvement in pneumatic springs



BEVAN 11111101100011 Car Spring. No. 111,303. Patented Jany 31,1871.

nil/I01 N. PETERS. Pnowuthn n her. Washington, D. c.

JOHN BEVAN, OF PORT RICHMOND, AND BENJAMTN W. HITOHOOOK, OF

WEST ELUSHING, NEW YORK.

Letters Patent No. 111,303, dated January 31, 1871.

lMPROVEMENT lN PNEUMATIC SPRINGS.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern Be it known that we, J OHN BEVAN, of Port Richmond, in the county of Richmond and State of New York, and BENJAMIN. W, Hrroncoorgnf West Flushing, in the county of Queens and State aforesaid, have inventeda new and useful Improvement in Pneumatic Springs; and we do hereby declare that the following is a full, clear, and exact description of the same, reference being bad to the accompanying drawing forming part of this specification, and in Figure 1 represents a vertical section ofa pneu- "matie spring constructed in accordance with our improvement, and

v Figure 2, a plan of the same.

Similar letters of reference indicate corresponding parts.

Our invention consists in a pneumatic spring, composed of three leading elements, namely-an outer flexible water-proofcase, made inelastic to prevent alteration of its form, an interior flexible or collapsible device, and an inflexible air-cylinder or chamber also arranged within the outer case and connected with the latter at its top', preferably by a surface or pressure plate, and in open communication with the collapsible device below. To give to this combination its vitality as a springon the pneumatic principle of action, the outer flexible case and interiorcollapsible device are both charged with a fluid, preferably afluid mixture incapable of freezing under natural exposure, so that, on weight or force being applied to the top of the outer case, the latter, in flexing, will cause thefluid'contained in it to produce a contraction of the inner flexible .device that thus, by the fluid contained in it, produces a compression of the air in the cylinder. A' pneumatic spring thus constructed is cheap, durable, and powerful, and exempt from the friction of sliding parts.

Referring to the accompanying drawing- A represents a close outer India-rubber shell or case, of a reduced size or diameter intermediately of its height, and of a thickness that, while admitting of its being flexed, renders it inelastic or incapable of beingstretched out of form so as to interfere with its act-ion.

Arranged within this flexible shell or case is a flexible andvcontractile or collapsible hollow device, B, of

within said outer case of an inflexible air-cylinder or chamber, 0. This air-cylinder or chamber is. connected with the top of the outer case by a surface or pressure plate, a, suitably attached by bolts to: an inner plate, and is in open communication at its bottom with theflexible hollow ball or collapsible device 13 that is secured to said cylinder, so as to be exempt from leakage.

The space I), surrounding the ball 13 and cylinder 0, also the interior of the ball B are both charged with a fluid which may be composed of glycerine and water to prevent freezin Any suitable simple or compound fluid, however, may be used. Upon weight or force being applied to the top, or, in fact, to either end, or both ends of the spring, the outer case A is flexed inward, which causes the fluid within it to compress the contractile or collapsible device B, the fluid in' which, in being displaced, com presses the air in the cylinder 0, thereby communicating to the spring its necessary pneumatic elasticity.

We do not restrict ourselves to any particular shape, either of the spring as a whole or of its par separately.

What is here claimed, and desired to be secured by Letters Patent, is

The combination of the outer flexible case A with the interior contractile or collapsible device 13 audinflexible air-cylinder or chamber 0, for operation with or through an interior fluid or mixture, substantially as specified.

JOHN BEVAN. BEN. W. HITC-HOOGK- Witnesses:

FRED. Hams, R. RABEAU. 

